Conformance testing is to see if the protocol implementation conforms to its specification. A lot of test sequences have been developed for testing centers. Yet directly applying these test sequences to the simple testing system in laboratories suffers from the frequently-occurred synchronization problems. This paper proposes a new technique to disconnect a test sequence into segments based on their functions, and reconnects them into a new test sequence that simulates these functions yet suffers less from the synchronization problems.

We study state feedback control of discrete event systems described by the Golaszewski-Ramadge model. We derive a necessary and sufficient condition for the existence of a balanced state feedback controller under partial observations.

A switched-capacitor phase-shifter oscillator of low distortion is discussed. The dc voltage related to the amplitude of oscillation was made for an automatic gain controller. The distortion factor was less than 0.5% in the frequency range from 100 µHz to 1 Hz.

It is usual to set single-point noise controller at each point in order to cancel noises at multiple cancelling points. How should we adapt controllers in such a case? The easiest way is to let them work individually, though it is possible to use all the error signals for one controller. In this case, there is a promblem that the controllers do not necessarily converge. In this paper, we consider the conditions of the paths under which the controllers converge when they work individually.

The first optimizing compiler was developed at IBM in order to prove that high level language programming could be as efficient as hand-coded machine language. Computer architecture and compiler optimization interacted through a feedback loop, from the high-level language computer architectures of the 1970s to the RISC machines of the 1980s. In the supercomputing community, the availability of effective vectorizing compilers delivered easy-to-use performance in the 1980s to the present. These compilers were successful at least in part because they could predict poor performance spots in the program and report these to users. This fostered a feedback loop between programmers and compilers to develop high performance programs. Future optimizing compilers for high performance computers and supercomputers will have to take advantage of both feedback loops.

This paper proposes a data-localization scheduling scheme inside a processor-cluster for multigrain parallel processing, which hierarchically exploits parallelism among coarsegrain tasks like loops, medium-grain tasks like loop iterations and near-fine-grain tasks like statements. The proposed scheme assigns near-fine-grain or medium-grain tasks inside coarse-grain tasks onto processors inside a processor-cluster so that maximum parallelism can be exploited and inter-processor data transfer can be minimum after data-localization for coarse-grain tasks across processor-clusters. Performance evaluation on a multiprocessor system OSCAR shows that multigrain parallel processing with the proposed data-localization scheduling can reduce execution time for application programs by 10% compared with multigrain parallel processing without data-localization.

In this paper, a block implementation of high-speed IIR adaptive noise canceller is proposed. First, the block difference equation of an IIR filter is derived by the difference equation for high-speed signal processing. It is shown that the computational complexity for updating the coefficients of IIR adaptive filter can be reduced by using the relations between the elements of coefficient matrices of block difference equation. Secondly, the block implementation of IIR adaptive noise canceller is proposed in which the convergence rate is increased by successively adjusting filter Q-factors. Finally, the usefulness of proposed block implementation is verified by the computer simulations.

In this paper, in order to achieve the low power consumption of programmable divider in a PLL frequency synthesizer, we propose a new prescaler method for low power consumption. A fixed prescaler is inserted in front of the (N +1/2) programmable divider which is designed based on the new principle. The divider ratio in the loop does not vary at all even if such a prescaler is utilized. Then the permissible delay periods of a programmable divider can be extended to two times as long as the conventional method, and the low power consumption and low cost in a PLL frequency synthesizer have been achieved.

A method is presented for implementing a neural control system for controlling a piezopolymer bimorph flexible micro-actuator. Two neural controllers were constructed, both with an adaptive-type neural identifier and a learning-type direct or open-loop neural controller, focusing on the difference in learning speed between the adaptive and learning schemes. Simulated use of the proposed controllers to control a flexible micro-actuator showed that they can do so effectively. Experiments also demonstrated that a neural controller can be used to control a flexible micro-actuator.

Force curves obtained from an elastic contact theory are shown and compared with experimental results. In the elastic contact theory, a pin-on-disk contact is assumed and the following interaction are taken into consideration; (i) elastic deformation, (ii) the specific energy of adhesion in the area of the contact, which is expressed as the difference between the surface energies and the interface energy, (iii) the long-range interaction outside the area of contact, assuming the additivity of the Lennard-Jones type potential, and (iv) another elastic term for the measurement system such as the cantilever stiffness of an atomic force microscope (AFM). In the limit when the stiffness is infinite, the theory conforms to Muller-Yushchenko-Derjaguin (MYD) theory. In the limit when the surface-surface interaction is negligible, the theory conforms to the analytical theory by Takahashi-Mizuno-Onzawa. In the limit when the stiffness is infinite and the long-range interaction outside the area of contact is negligible, the theory conforms to Johnson-Kendall-Roberts (JKR) theory. All parameters and all equations are normalized and the normalized force curve is obtained as the functional of only two parameters; (1) the normalized stiffness of the measurement system, and (2) the normalized distance which is used in the expression of the Lennard-Jones potential. The force-displacement plots are converted into force-penetration plots.

Resonance characteristics of a coupled dielectric resonator which consists of a Whispering Gallery mode dielectric disk resonator and a ring resonator located eccentrically are analyzed. New analytical results of resonance characteristic based on the distributed coupling phenomena between the disk and the ring are obtained. The resonance performances have also been verified experimentally on X band model. We have found that Free Spectral Range of the coupled resonator is several times larger than that of the single disk resonator and the single ring resonator, respectively. As a result, the eccentric coupled resonator discussed in this paper can be used as a frequency selective element in millimeter wave integrated circuits.

A fault in multi-processing system arbitration circuits result in incorrect arbitration or abnormal operation of the system. A highly reliable system requires dependable arbitration in order to operate properly. Previously, we proposed alternate competing arbitration suitable for highly reliable systems. In this paper, we propose a method for improvement of fault detection and location using additional checkers. This method is effective to maintain reliability of the system.

In this paper we propose a method of formal verification of totally self-checking (TSC) properties of combinational circuits using logic function manipulation. We show that the problem of verification of TSC properties can be transformed to a satisfiability problem of decision functions formed from characteristic functions of a circuit's output code words. Then the problem can be solved using binary decision diagrams (BDD). Experimental results show the effectiveness of the proposed method.

We describe the design, fabrication, and characteristics of FDM/WDM coupler deposited by TEOS-O3 based APCVD method on silicon substrates. Due to drastically reduced birefringence by APCVD process, completely polarization independent narrow band (100 GHz) Mach-Zehnder type FDM coupler was obtained. We also fabricated 1.3/1.55 µm directional coupler type WDM coupler with very low insertion loss.

The fault tolerant computer (FTC) is applied as a communication or database server in the information service and computer aided process control fields. User requires of the FTC are to provide the current level of performance and software transparency needing no additional dedicated program for fault tolerance. To meet these requirements, we propose quadprocessor redundancy (QPR) architecture that combines dualRISC based duplicated CPUs integrating main memories, and duplicated I/O subsystems by using some additional hardware. Duplicated CPUs run under the instruction level synchronization (lock step operation) , and the duplicated I/O subsystems are managed by an operating system. When a fault is detected, the faulty CPU is isolated by hardware. User program is continuously executed by the remaining CPU. We applied the QPR to our UNIX servers, and achieved satisfactory levels of performance.

This paper presents a reshufflable and laziness tolerant mental card game protocol. First, our protocol can reshuffle any subset of cards. For example, some opened cards and some face down cards can be shuffled together. Next, we consider two types of honest players, currently active and currently nonactive. A player is currently nonactive if he dropped out the game or he declared "pass" and has not declared "rejoin" yet. In the proposed protocol, if more than half of the players are currently active, they can play the game. In this case, the privacy of the currently nonactive players are kept secret.

The design, fabrication, and testing of a highly multimode polymeric 88 star coupler is described. The design process allowed a comparison to be made of ray tracing and beam propagation methods for the design of such highly multimode waveguide devices. The results obtained with either of these two different methods agree well with actual measurements on a fabricated 88 multimode-input star coupler with a refractive index difference of Δn=0.0274 and a device length of L=4.25 cm. The reduction in the rms power fluctuation in the output guides with the choice of a higher refractive index difference is demonstrated.

When wireless multi-media information which includes speech, image, data and so on are transmitted, the defference in information rate, required quality as well as traffic performance should be taken into account. A wireless spread spectrum system can achieve a flexible balance of these differences because of the inherent asynchronous capability of CDMA. In this paper, we propose a wireless multi-media CDMA system based on a processing gain control in a dynamic traffic channel. According to the priority of each medium and channel measurement information i.e. traffic, the optimal processing gain can be controlled by using Nonlinear Programming. Numerical results demonstrate that the proposed method possesses higher flexible capacity than TDMA in a dynamic multi-medea traffic channel.

A generalized Reed-Muller expression (GRM) is obtained by negating some of the literals in a positive polarity Reed-Muller expression (PPRM). There are at most 2(n2)^(n-1) different GRMs for an n-variable function. A minimum GRM is one with the fewest products. This paper presents certain properties and an exact minimization algorithm for GRMs. The minimization algorithm uses binary decision diagrams. Up to five variables, all the representative functions of NP-equivalence classes were generated and minimized. Tables compare the number of products necessary to represent four-and five-variable functions for four classes of expressions: PPRMs, FPRMs, GRMs and SOPs. GRMs require, on the average, fewer products than sum-of-products expressions (SOPs), and have easily testable realizations.

We propose a novel feeding circuit for a 30 GHz planar multibeam antenna applied to high-speed wireless communication systems. The feeding circuit is a bi-layer 8-port Butler matrix constructed with phase adjusted slot-coupled hybrids and branch-line hybrids. The new circuit configuration eliminates troublesome vias and line crossings, so it can be manufactured by traditional photolithograph. The feeding circuit is designed by using the spectral domain moment method considering bonding film effects. A prototype of a multibeam antenna which has seven pencil-beams with 10 beamwidths is manufactured and tested; the beam scan angle error is less than 3 at 30 GHz.